Plywood shaping apparatus



Sept. 4, 1951 w. E. RADlG 2,567,122

PLYWOOD SHAPING APPARATUS Filed Oct. 19, 1946 2 Sheets-Sheet -l /2 2INVENTOR.

P 1951 w. E. RADIG PLYWOOD SHAPING APPARATUS 2 Sheets-Sheet 2 Filed Oct.19, 1946 Patented Sept. 4, 1951 Walter E. litadig, Chicago, 111.,cassignor to Bell .& Howell Company, '.Chicago, :Ill., a corporation ofIllinois Application October'19, 1946,"Sei'ial No."704,392

. 4= Claims.

iMy'invention relates particularly to apparatus for "forming blanks of 1pliable -materia1 and more particularlyfor forming blanks of laminatedma- 'terialsuch' asDlyWood-the invention contemplatingthe-forming oflaminated blanks the adhesive or-bond'between-t-he*laminations of which,is set =01 cured as'an'inciden-t oi'the forming operation.

v()"bj'ectsof the'invention-reside in the provision "of'a'novel, simpleand 'e'fiective formingapparatus, which is particularly adapted forforming plywood *blanks' th-e adhesive or bond between the "laminationsof which, is set or cured as an'inci- "'dent"'of 'the'forming-operation,which develops adequate and properly "distributed forming pressure,which is convenient-in use, which lends itself tom'ass production, whichis comparatively :ishapes.

The invention will 'be'better understood by referenceto'the accompanyingdrawing-forming a part. hereof and in which Figure "l'is perspectiveview of a forming apparatus embodying my invention and showing it informing condition;

Figure 2.is ai'front elevation of the same'show- .ing it in open or.blankieceiVing condition;

Figured is .afront elevation of' the same showing it in preliminaryblank forming condition;

Figure 4 isafront elevation of the same showing it in'ffinalblank'forming condition;

Figure 5.'is a partial section on the line -5.0f

Figure 4 and Figure 6 is a partial section on the line v6-'5.0f Figure1.

"Referring to the drawing, a base, designated at l, is,,pr.ovided withan elongated topi2 and with .wheenm castersl3 by means of which it maybe conveniently moved about. A cradled is. secured downwardly on theintermediate portion of the top 2 and the top surface 5 .of the cradleis condownwardly upon the surface 5 and curved correspondinglytherewith. "Three outer form-members'B of suitable material such .aswood, overlie .the tension member 6 and are arranged in ad-.. jjacentlyspaced succession along the same. TI'he .tension member engagingsurfacese of'these --formmembersare convex longitudinally of the.tension. member and correspond in radiuswith the curvature of theintermediate portion 7 of the .tension member, and .the intermediate ofthe ,ior-m members engages inthe curvature .of the in- .termediate.portion of .the .tension member .-.and

is secured together-with .the .tension. member downwardly on the surface5.0f thecradle. .The.

endportions of the tension member extend out- Cl. 31 44.2fi.5

- 2 -wardly beyond'the outer-form members and are doubled'back andsecured, as designated atil I, to form closed loops I2 through whichclamping 'rods l3 extend, these clamping rods projecting from both sidesof :thetension member. "The surfaces l4 of the outer form members "8,opposite the tension member engaging surfaces 9, comprise the formingsurfaces of these form members and are fiat, and a flexible 10 metalform member 15, extending correspondingly withthetension memberfi,overlies the-forming surfaces 14 and extends between adjoining ends ofthese form members and is secured in a usual manner with each of theform members fl. Noting that the top 2' of the'base underlies thetension member '6 and that the tension member, the outer form members 8and the flexible form member i5 arearranged to extend lineally of thetop and that the intermediate portion l of'the tension member, theintermediate of the form 'n iembers 8 and-the intermediate portion ofthe flexible form member are secured with the base *1, support blocks[-6 secured on the top-2 adjacent the ends thereof are adapted tosupport-the tenvn sion members, outer form members and flexible 'formmember in generally flat condition, as shown in Figure 2, in whichcondition a blank ll of pliable material in unformed orflat conditionis-pl-aced ontop ofthe flexible form member for 0 the forming thereof.

An inner form I8 of suitable material such as wood and which as shown isof generally rectan- =gular form, is provided with a forming surfaceextending-partially thereabout and having a metal 5-"sheet l9 overlyingthe same and secured to-the =in ner for-m, thefor-mingsurface comprisingthree angularly related flat forming surface portionsZfl respectivelycorresponding with the forming suri-aces -M of the outer form membersand arranged 40 in a U-shapeandconvexly curved corn-er forming surfaceport-ions zl-between adjacent ends of the "surface portionsifl. Thesurface 22 of the inner form between the ends of the forming surface"thereof is convex peripherally of the inner form. With the blank llplaced as aforesaid, thein ner form 18 is placed on top of the blankwith the intermediate of the forming surface portions 20 -of the innerform registered with the forming -suriacel4- of' the intermediate of theouter form "members-8, as "shown in Figure 2, preparatory to "theforming operation. This registration is pre- 'de.terminatelyefiected bylocating lugs 23 secured 'on'opposite sides of the inner form [8 andprojecting outwardlyfrom the intermediate of the forming surfaceportions Zfioithe inner form and slidably' engageable between pairs ofspaced lugs 24 secured on opposite sides of the intermediate of (theouter form members 8, the lugs cooperat- "ingito predeterminately locatethe intermediate fi portionof theformin'g surface of the inner form withthat of the tension member 6 and the flexi- 3 ble form member [5 and theintermediate of the outer form members 8.

With the blank I! and the inner form l8 so placed, the forming operationis effected by wrapping the tension member 6 and with it the outer formmembers 8 and the flexible form member l5 about the inner form and blankand lineally tensioning the tension member, as shown in Figures 1 and 4,to apply forming pressure to the blank. When the outer form members arein forming relation with the inner form, the forming surfaces 14 of theouter form members 8 lie opposite the forming surface portions 23 of theinner form 18 and the convex tension member engaging surfaces 9 of theouter form members and the convex surface 22 of the inner form generallconform with a circle so that the tension member is generally conformedwith this circle and the forming pressure is properly distributed overthe area of the blank being formed, it being observed that as thetension member is tensioned as hereinafter described, the end loops l2thereof engage inwardly against the convex surface 22 of the inner form,or the clamping rods l3 have an equivalent engagement as hereinafterdescribed, to exert pressure on the portion of the blank between theintermediate of the forming surface portions 20 of the inner form andthe forming surface l4 of the intermediate of the outer form members 3,and it also being observed that as the tension member is tensioned, theend members of the outer form members 8 are drawn away from theintermediate of the outer form members in the direction toward the endsof the forming surface of the inner form by reason of the coaction ofthe tension member with the convex tension member engaging surfaces 9and with the convex surface 22 of the inner form, so that the portionsof the flexible form member l5 opposite the corner forming surfaceportions 2| of the inner form are wrapped and tensioned about thecorresponding portions of the blank, see particularly Figure 6, to exertadequate forming pressure throughout these portions of the blank andwhen a plywood,

blank is being formed and prevent fracture of the outer lamination orlaminations of the blank.

Two retaining members 25 are secured on opposite sides of the inner form[8 in the region of the convex surface 22 and extend lineally of thecurvature thereof, and the opposite end portions of the retainingmembers are provided with spaced opposing retaining latches 26 extendingoutwardly from the surface 22. The retaining latches are operative onthe ends of the tension member 6, by reason of the projecting ends ofthe clamping rods [3 being engageable therewith, to retain the tensionmember and outer form members 8 in a preliminary forming rela tion withthe inner form I8 and blank I? into which they are movable against onlya small degree of resistance from the blank, as shown in Figure 3, thisarrangement providing for the tension and outer form members beingmanually moved into and retained in such preliminary forming relation inwhich the clamping rods are desirably adj acently spaced for cooperationwith clamping means hereinafter described for further drawing the endsof the tension member together and bringing the inner and outer formmembers into final forming relation and exerting pressure on the blankI! as shown in Figures 1 and 4. The surfaces 21 of the retaining members25 between the retaining latches 2B, which correspond with the convexsurface 22 of the inner form, are convex in concentric relation with thesurface 22 and form offset continuations of the surface 22, and the endloops 12 of the tension member engage inwardly against the convexsurface 22 and/or the projecting ends of the clamping rods 13 engageinwardly against the convex surfaces 21 from the time the tension andouter form members are in said preliminary forming relation until theyare in final forming relation with the inner form to exert pressure onthe portion of the blank I! between the intermediate of the formingsurface portions 20 and the intermediate of the outer form members 8.

With the tension member 6 and the outer form members 8 in the aforesaidpreliminary forming relation, as shown in Figure 3, the apparatus ispositioned in proper relation with a power clamping device, not shown,and oppositely acting clamping members 28 and 29 of the power clampingdevice are respectively detachably oppositely engaged with theprojecting ends of the clamping rods l3, as designated at 3| and 32 inFigure l, and the power clamping device is energized to draw theclamping rods together and so tension the tension member.

Additional or final manually operable clamping means is provided fortensioning the tension member 6 and maintaining the same in tensionedcondition until the blank is set in formed condition, it being observedthat the apparatus is intended for the forming of plywood blanks theadhesive or bond between the laminations of which isnot set or curedprevious to the forming operation and is set or cured as an incident ofthe forming operation and while the blank I! is maintained underpressure in formed condition by the apparatus.

The additional or final clamping means shown consists of two screwclamps, see Figures 1, 4 and 5, and each clamp comprises two pairs oflevers 33 corresponding ends of which are pivotally connected by meansof a stud 34 extending between the pairs of levers and having reducedends 35 thereof pivotally engaged in apertures 36 through the levers,retaining washers 31 secured on the ends of the stud by screws 38 toretain the levers engaged on the stud, two studs 39, respectivelyextending between the pairs of levers adjacent the free ends of thelevers and pivotally connected therewith in a manner similar to themanner in which the stud 34 is connected with the levers, a clampingscrew 4| screwthreaded diametrically through the intermediate portionsof the studs 39 respectively with right and left hand threads 42 and 43,and opposing clamping rod engaging recesses 44 on the free ends of thepairs of levers.

With the tension member 6 tensioned by the power clamping device, seeFigure 1, the two screw clamps are connected with the clamping rods l3by engagement of the opposing recesses 44 of the pairs of levers 33respectively with the clamping rods and the clamping screws 4| arerotated to cause the pairs of levers to draw the clamping rods togetherand exert tension on the tension member 6. The two screw clamps aredisposed respectively in the regions of opposite sides of the tensionmember and the inner pairs of clamping levers 33 extend through slots 45in the tension member to engage the clamping rods.

After the tension member 6 has been tensioned by the screw clamps, thepower clamping device is deenergized and the clamping members 28 and 29are disengaged from the clamping rods 13, so that the apparatus, withthe tension member 6 tensioned by the screw clamps as shown in Figure 4,may be moved away from the power clamping device to another location,the power clamping device being thus released for further use.

For the purpose of setting or curing the adhesive or bond between thelaminations of the blank ll while it is maintained under pressure and informed condition in the apparatus, the flexible metal form member l5overlying the form surfaces 14 of the outer form members 8 and the metalsheet 19 covering the forming surface of the inner form It, which areelectrically insulated from each other, form opposing electrodes bymeans of which an electrostatic field is set up, embracing the formedblank as it is maintained under forming pressure in the apparatus, whenthe members I5 and I9 are connected to opposite poles of a source ofhigh frequency electric current, so that the adhesive or bond betweenthe laminations of the formed blank are quickly set or cured bydielectric heating, the members 15 and I9 being provided with terminals,designated res ectively at 46 and 41, for the purpose of energizing thesame.

After the forming and setting or curing operations are completed thescrew clamps are released and disconnected from the clamping rods I3, sothat the formed blank may be removed from the apparatus preparatory toanother forming operation.

While I have thus described my invention, I do not wish to be limited tothe precise details described, as changes may be readily made withoutdeparting from the spirit of my invention, but having thus described myinvention, I claim as new and desire to secure by Letters Patent thefollowing:

1. In a forming apparatus, the combination of an inner form providedwith a forming surface comprising a succession of angularly relatedforming surface portions of relatively flat character, a flexibletension member, a plurality of outer form members secured in successionand arranged along said tension member in such relation as torespectively lie opposite said forming surface portions for forming ablank disposed between said inner form and outer form members when saidtension member and with it said outer from members are wrapped aboutsaid inner form and blank, the forming surfaces of said outer formmembers being of relatively flat character and the tension memberengaging surfaces of said outer form members being convex longitudinallyof said tension member and generally conforming with a circle when saidouter form members are in forming relation with said inner form, and areleasable clamp operative on the ends of said tension member tolineally tension the same with said tension member and outer formmembers wrapped about said inner form and blank.

2. In a forming apparatus, the combination of an inner form providedwith a forming surface comprising a succession of angularly relatedforming surface portions of relatively flat character, a flexibletension member, a plurality of outer form members secured in successionand arranged along said tension member in such relation as torespectively lie opposite said forming surface portions for forming ablank disposed between said inner form and outer form members when saidtension member and with it said outer form members are wrapped aboutsaid inner form and blank, the forming surfaces of said outer formmembers being of relatively flat character and the tension memberengaging surfaces of said outer form members being convex longitudinallyof said tension member and generally conforming with a circle when saidouter form members are in forming relation with said inner form, aregistering device operative to predterminately locate the intermediateportion of said forming surface with said outer form members, and areleasable clamp operative on the ends of said tension member tolineally tension the same with said tension member and outer formmembers wrapped about said inner form and blank.

3. In a forming apparatus, the combination of an inner form providedwith a forming surface extending partially thereabout and comprising asuccession of angularl related forming surface portions of relativelyfiat character, a flexible tension member, a pluarlity of outer formmembers arranged in succession along said tension member, a flexibleform element disposed at the forming surfaces of and extending betweenadjoining ends of and secured with said outer form members, said outerform members being arranged in such relation as to respectively lieopposite said forming surface portions for forming a blank disposedbetween said inner form and said outer form members and flexible formelement when said tension member and with it said outer form members andflexible form element are wrapped about said inner form and blank, theforming surfaces of said outer form members being of relatively flatcharacter and the tension member engaging faces of said outer formmembers being convex longitudinally of said tension member and thesurface of said inner from between the ends of said forming surfacebeing convex peripherally of said inner form and said convex surfacesgenerally conforming with a circle when said outer form members andflexible form element are in forming relation with said inner form, anda releasable clamp operative on the ends of said tension member tolineally tension of the same with said tension member and outer formmembers and flexible form means wrapped about said inner form and blankand with said tension member bearing inwardly against said secondmentioned inner form surface.

4. In a forming apparatus, the combination recited in claim 3 andfurther characterized in that said flexible form element is ofelectrically conductive material and overlies the forming surfaces ofsaid outer form members, and that a sheet of electrically conductivematerial overlies said forming surface of said inner form and that it iselectrically insulated form said flexible form element.

WALTER E. RADIG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 115,536 Smith et al. May 30, 1871220,229 Flora Oct. '7, 1879 229,198 Steinway June 22, 1880 874,406Johnson Dec. 24, 1907 1,234,665 Hice July 24, 1917 2,307,344 Zottu Jan.5, 1943 FOREIGN PATENTS Number Country Date 97,957 Germany July 30, 1898

